https://blogs.oracle.com/bill/entry/ditto_blocks_the_amazing_tape Probably most of you already know about this, but for those of you who haven't the above describes ZFS "ditto blocks" which is a good feature we need on BTRFS. The briefest summary is that on top of the RAID redundancy there is one more copy of metadata than there is of data, so copies=2 implies 3 copies of metadata and the default option of 1 copy of data means that metadata is "dup" in addition to whatever RAID redundancy is in place. -- My Main Blog http://etbe.coker.com.au/ My Documents Blog http://doc.coker.com.au/ -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html